THURSDAY, July 30, 2015 (HealthDay News) -- Older smokers who experience migraines appear to be at increased risk of stroke, a new study suggests.

The study included nearly 1,300 people, average age 68, who suffered migraine headaches with and without aura. Migraine with aura is a migraine that's preceded or accompanied by visual effects such as flashes of light or blind spots, or by tingling in the hands or face.

The study participants were followed for an average of 11 years to see how many had a heart attack or stroke. The findings were published online July 22 in the journal Neurology.

The researchers did not find an association between migraine and the risk of either heart attack or stroke in nonsmokers. But among smokers, migraine was associated with a threefold increased risk of stroke.

However, even though the study found an association between migraine and stroke risk in smokers, it did not prove a cause-and-effect relationship.

"Statistically, we could not rule out the possibility that the relationship between migraine and stroke in smokers was due to chance, however, we believe the association is consistent with other studies," study author Dr. Teshamae Monteith said in a journal news release. Monteith is director of the headache program at the University of Miami Miller School of Medicine.

"Our findings may provide more evidence as to why quitting smoking is important for people who experience migraine," she added.

"While this investigation of migraine and vascular events in older people found that only smokers with migraine have an increased risk of stroke, earlier studies have shown that women younger than 45 who have migraine with aura are also at an increased risk of stroke, whether or not they smoke," Monteith said.